a)\(\frac{5}{9}\times x-1=\frac{8}{9}\)

\(\frac{5}{9}\times x=\frac{8}{9}+1\)

\(\frac{5}{9}\times x=\frac{17}{9}\)

\(x=\frac{17}{9}:\frac{5}{9}\)

\(x=\frac{17}{5}\)

b)\(x+x\times\frac{1}{3}:\frac{2}{9}+x:\frac{2}{7}=252\)

\(x+x\times\frac{3}{2}+x:\frac{2}{7}=252\)

\(x.1+x.\frac{3}{2}+x.\frac{7}{2}=252\)

\(x\left(1+\frac{3}{2}+\frac{7}{2}\right)=252\)

\(x\times6=252\)

\(x=252:6\)

\(x=42\)

a,5/9.x-1=8/9

5/9.x=17/9

x=17/5

b,x+x.1/3:2/9+x:2/7=252

x+x.1/3.9/2+x.7/2=252

x(1+1/3.9/2+7/2)=252

x.6=252

x=42

X=1/6

x=15/14

x=5/6-2/3

x=1/3

x=3/7:2/5

x=15/14

\(x=\dfrac{5}{6}-\dfrac{2}{3}=\dfrac{1}{6}\)

\(x=\dfrac{3}{7}:\dfrac{2}{5}=\dfrac{15}{14}\)

4/5 x X = 40/33

X = 40/33 : 4/5

X = 50/33

x= ( 10/11 : 3/4 ) : 4/5 = 50 /33

a: =>x:1/2=5/9

=>x=10/9

b: =>x*2/5=7/3

=>x=7/3:2/5=7/3*5/2=35/6

c: =>x=7/8-9/16=5/16

a) 213 - 2 x X = 47

2 x X = 213 - 47

2 x X = 166

X = 166 : 2 

X = 83

b) 3 x ( X + 1 ) - 300 = 906

3 x ( X + 1 ) = 906 + 300

3 x ( X + 1 ) = 1206

X + 1 = 1206 : 3

X + 1 = 402

X = 402 - 1

X = 401

c) \(\frac{7}{3}-\frac{2}{3}\times x=\frac{1}{4}\)

\(\frac{2}{3}\times x=\frac{7}{3}-\frac{1}{4}\)

\(\frac{2}{3}\times x=\frac{25}{12}\)

\(x=\frac{25}{12}:\frac{2}{3}\)

\(x=\frac{25}{8}\)

d) \(\frac{2}{5}\times x+\frac{7}{8}=2\)

\(\frac{2}{5}\times x=2-\frac{7}{8}\)

\(\frac{2}{5}\times x=\frac{9}{8}\)

\(x=\frac{9}{8}:\frac{2}{5}\)

\(x=\frac{45}{16}\)

Học tốt #

a) \(213-2\cdot x=47\)\(\Leftrightarrow2\cdot x=166\Leftrightarrow x=83\)

b)\(3x\left(x+1\right)-300=906\Leftrightarrow3x\left(x+1\right)=606\)

\(\Leftrightarrow x\left(x+1\right)=202\Leftrightarrow x^2+x-202=0\)

\(\Leftrightarrow\left(x+\frac{1}{2}\right)^2-202,25=0\)\(\Leftrightarrow\orbr{\begin{cases}x+\frac{1}{2}=\sqrt{202,25}\\x+\frac{1}{2}=-\sqrt{202,25}\end{cases}}\)

\(\Leftrightarrow\orbr{\begin{cases}x=\sqrt{202,25}-0,5\\x=-\sqrt{202,25}-0,5\end{cases}}\)

a) 213 - 2*x = 47

2*x  = 213 - 47

2*x = 126

x = 63

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